'Cached' vs. 'Buffers' memory

Hi, What exactly is the difference between 'Cached' and 'Buffers' memory (as seen in /proc/meminfo and reported by free)? I have an application that reads large BerkeleyDB style database files. Where would I see the reads cached under, 'Cached' or 'Buffers'? Sorry if this not a list for this type of questions, but I can't get an answer anywhere else. Thanks in advance to everyone who replies! Eugene.